Penetrating sealers (includes silanes, siloxanes, silicates, and siliconates) | Penetrate and react chemically within the capillaries of the concrete to shield against moisture penetration and deicing chemicals. | Exterior concrete surfaces subject to corrosion and freeze-thaw damage Where a natural, matte finish is desired | Provide invisible protection without changing the surface appearance or leaving a sheen. | Provide excellent protection against outdoor exposure conditions. Most products are also breathable, allowing moisture vapor to escape. |
Acrylics | Form a thin protective film on the concrete surface. Available in both solvent- and water-based formulations | Both exterior and interior concrete On projects where easy application and economy is important To enhance the beauty of colored, stamped or exposed- aggregate concrete On fast-track projects, since acrylics often dry to the touch within an hour | Available in a range of sheen levels. Solvent-based acrylics generally enhance color better than water-based products. | Provide good protection against water and chloride intrusion, but usually wear faster than polyurethanes and epoxies.Solvent-based acrylics generally perform better than water-based products for outdoor use. On indoor surfaces, softer acrylic sealers usually require regular maintenance with several coats of a sacrificial floor finish, or wax, to prevent wear and black heel marks. |
Polyurethanes | Form a high-build protective film on the concrete surface. Available in both solvent- and water-based formulations | Both exterior and interior concrete On floors in high-traffic areas, to provide good resistance to scuffs and staining To enhance the beauty of colored, stamped or exposed- aggregate concrete Concrete countertops | Available in a range of sheen levels. Finish is transparent and non-yellowing. | Nearly twice as thick as acrylic sealers, and produce a very durable chemical- and abrasion-resistant finish. Most urethanes are moisture intolerant until they cure, so no water should be present on the surface when the sealer is applied. |
Epoxies | Form a high-build protective film on the concrete surface. Most are two-component products mixed prior to application. | On floors in high-traffic areas Cement-based overlays Concrete countertops May yellow with UV exposure, so generally limited to interior use | Available clear or pigmented, if you wish to add color. Most products impart a glossy finish. |
Source: www.concretenetwork.com